How hot is too hot?

[AThoele]

Hi! I was just wondering whether someone can tell me how hot is too hot for orchids (phals, specifically) to be outside. I read that they like temps between 75-85 during the day. I'm in Florida and today was especially hot. There was a heat advisory and we're probably around 104 with the heat index right now. I usually leave the orchids on my back porch since I don't get very good sun in my apartment. I brought them in earlier, but I won't always be here in the middle of the day to move them inside. Would they be OK if I left them out there - assuming they're in the shade? Or should I only leave them outside at night for now?

[nhman]

First off - it is the actual AIR temperature that is more important. The "Heat index" is more of a measurement of how hot an animal appreciates the air to be and is a combination of the humidity and air temperatures - an artificial measurement actually, like "wind-chill" (which you don't have a problem with in FLA)
Secondly - is the factor of air movement. The higher the air temperature, the better the surrounding air movement should be. This helps cool the plants.

Phals would not appreciate direct sun, so shade to part shade is a good choice.

Lastly, IF the actual air temps are a max of 85 degrees, they would likely be OK, but probably wouldn't like it any warmer.
Hope that helps!

[King_of_orchid_growing:)]

Temperatures over 100 isn't usually the problem. Some Phals come from places that warm.

But you gotta remember where they come from...

They grow on tree trunks and branches growing in dense forests that provide sufficient shade. It's also humid where they are. Many lowland Phals are growing in swamps or by rivers. Sometimes those rivers are quite large.

Also, if the air circulation around the area is good, then you shouldn't be having problems.

You may also have to water a bit more. Be careful though.

[AThoele]

The actual high today is supposed to be 99, but there has been a pretty good breeze all day. And the humidity has been between 70 and 80% lately. So I guess they'll be OK outside in the shade. Watering was my other concern. I just watered all my orchids this morning, but the three with good roots are already dry. I'm keeping a wood skewer in the pot so I know when to water. My problem before was that I was overwatering, but now I'm afraid that I'm underwatering. When I water, it seems like the water just runs out the bottom so I don't know how much the bark is actually holding on to. I've read about soaking. Is this a better option if they're drying out too quickly?

[camille1585]

I don't live in a climate nearly as hot as yours, but I've noticed that soaking does help keep the roots wet longer. In the winter I usually just water with a jug, and in late spring to early fall I soak. I soak them about 20 minutes, to give the roots and medium plenty of time to absorb water. I have clear pots, so as soon as I see that the roots have become all silver, it's time to water again.

[Cookiemonster]

I grow in arizona we're expecting a week full of 106 ,
Anyhow I keep my babies inside (75-90F) because I fear 100+ for phals isnt a great idea, But if you can keep humidity up and air movement I cant see it being a problem unless its prolonged intense heat.
If they are species I'd be careful especially if this is not within their temp and humidity range-

My advice to you, is in this incredible heat, the plants will dry out FAST, depending on what you have them in, I'd keep them shaded and you will probably have to water more frequently, also increasing air movement will keep them a bit cooler.

[nutgirl]

I grow in a small greenhouse that I'm able to keep at about 90-95 degs on a hot day (100+) I have fans going and try to keep the humidity at 50%. My phals seem to love it. I do have to soak them frequently. They grow like weeds.

My Dends and Catts are also happy. I put my Oncidiums in a lower level and nearer the fans.

I have forgotten the fans a time or two and it's gotten to 100+, but not for long, and I really soak everything good when that happens.

No obvious ill effects.

Maureen

[Jkelee]

Hi there, I live in FL too, further south. And YES IT IS HOT DOWN HERE!!!
I have about 400+ chids, all kinds outside in the burning sun, but in a shaded area, my chid hotel.
They are sooo hot, but they stay happy I guess.
I mist them in the mornings, and water in the afternoons. They get NO direct sunlight.
It's been 98-102 lately, with that heat index of 107-109!!
I'm sure yours will be just fine

[Nokomis.FL]

I watered mine this morning and was surprised that some were very moist. The high humidity is keeping them from drying out. Actually have some rot on some smaller Catestinae.

[seamonkey]

During the recent heat wave in Vancouver, my house went from 70 to 90 in one day. My newest phal dropped all its buds and flowers within two days. It was horribly disappointing! This may be more a function of the rapid change than of the absolute temperature, though.